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-rw-r--r--misc/pascal/insn16/popt/pcopt.c1811
1 files changed, 906 insertions, 905 deletions
diff --git a/misc/pascal/insn16/popt/pcopt.c b/misc/pascal/insn16/popt/pcopt.c
index 5af19002c..5f8deed80 100644
--- a/misc/pascal/insn16/popt/pcopt.c
+++ b/misc/pascal/insn16/popt/pcopt.c
@@ -1,905 +1,906 @@
-/**********************************************************************
- * pcopt.c
- * Constant Expression Optimizations
- *
- * Copyright (C) 2008 Gregory Nutt. All rights reserved.
- * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * 3. Neither the name NuttX nor the names of its contributors may be
- * used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- **********************************************************************/
-
-/**********************************************************************
- * Included Files
- **********************************************************************/
-
-#include <stdio.h>
-
-#include "keywords.h"
-#include "pdefs.h"
-#include "pinsn16.h"
-
-#include "paslib.h"
-#include "popt.h"
-#include "polocal.h"
-#include "pcopt.h"
-
-/**********************************************************************/
-
-sint16 unaryOptimize(void)
-{
- sint16 nchanges = 0;
- register uint16 temp;
- register sint16 i;
-
- TRACE(stderr, "[unaryOptimize]");
-
- /* At least two pcodes are need to perform unary optimizations */
-
- i = 0;
- while (i < nops-1)
- {
- /* Check for a constant value being pushed onto the stack */
-
- if ((pptr[i]->op == oPUSH) || (pptr[i]->op == oPUSHB))
- {
- /* Turn the oPUSHB into an oPUSH op (temporarily) */
-
- if (pptr[i]->op == oPUSHB)
- {
- pptr[i]->op = oPUSH;
- pptr[i]->arg2 = pptr[i]->arg1;
- pptr[i]->arg1 = 0;
- } /* end if */
-
- switch (pptr[i+1]->op)
- {
- /* Delete unary operators on constants */
- case oNEG :
- pptr[i]->arg2 = -(pptr[i]->arg2);
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oABS :
- if (signExtend16(pptr[i]->arg2) < 0)
- pptr[i]->arg2 = -signExtend16(pptr[i]->arg2);
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oINC :
- (pptr[i]->arg2)++;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oDEC :
- (pptr[i]->arg2)--;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oNOT :
- pptr[i]->arg2 = ~(pptr[i]->arg2);
- deletePcode(i+1);
- nchanges++;
- break;
-
- /* Simplify binary operations on constants */
-
- case oADD :
- if (pptr[i]->arg2 == 0)
- {
- deletePcodePair(i, (i+1));
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i+1]->op = oINC;
- deletePcode(i);
- nchanges++;
- } /* end else if */
- else if (pptr[i]->arg2 == (uint16)-1)
- {
- pptr[i+1]->op = oDEC;
- deletePcode(i);
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oSUB :
- if (pptr[i]->arg2 == 0)
- {
- deletePcodePair(i, (i+1));
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i+1]->op = oDEC;
- deletePcode(i);
- nchanges++;
- } /* end else if */
- else if (pptr[i]->arg2 == (uint16)-1)
- {
- pptr[i+1]->op = oINC;
- deletePcode(i);
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oMUL :
- case oDIV :
- temp = 0;
- switch (pptr[i]->arg2)
- {
- case 1 :
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
- case 16384 : temp++;
- case 8192 : temp++;
- case 4096 : temp++;
- case 2048 : temp++;
- case 1024 : temp++;
- case 512 : temp++;
- case 256 : temp++;
- case 128 : temp++;
- case 64 : temp++;
- case 32 : temp++;
- case 16 : temp++;
- case 8 : temp++;
- case 4 : temp++;
- case 2 : temp++;
- pptr[i]->arg2 = temp;
- if (pptr[i+1]->op == oMUL)
- pptr[i+1]->op = oSLL;
- else
- pptr[i+1]->op = oSRA;
- nchanges++;
- i++;
- break;
-
- default :
- i++;
- break;
- } /* end switch */
- break;
-
- case oSLL :
- case oSRL :
- case oSRA :
- case oOR :
- if (pptr[i]->arg2 == 0)
- {
- deletePcodePair(i, (i+1));
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oAND :
- if (pptr[i]->arg2 == 0xffff)
- {
- deletePcodePair(i, (i+1));
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- /* Delete comparisons of constants to zero */
-
- case oEQUZ :
- if (pptr[i]->arg2 == 0) pptr[i]->arg2 = -1;
- else pptr[i]->arg2 = 0;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oNEQZ :
- if (pptr[i]->arg2 != 0)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oLTZ :
- if (signExtend16(pptr[i]->arg2) < 0)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oGTEZ :
- if (signExtend16(pptr[i]->arg2) >= 0)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oGTZ :
- if (pptr[i]->arg2 > 0) pptr[i]->arg2 = -1;
- else pptr[i]->arg2 = 0;
- deletePcode(i+1);
- nchanges++;
- break;
-
- case oLTEZ :
- if (pptr[i]->arg2 <= 0) pptr[i]->arg2 = -1;
- else pptr[i]->arg2 = 0;
- deletePcode(i+1);
- nchanges++;
- break;
-
- /* Simplify comparisons with certain constants */
-
- case oEQU :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oEQUZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i]->op = oDEC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oEQUZ;
- nchanges++;
- } /* end else if */
- else if (signExtend16(pptr[i]->arg2) == -1)
- {
- pptr[i]->op = oINC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oEQUZ;
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oNEQ :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oNEQZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i]->op = oDEC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oNEQZ;
- nchanges++;
- } /* end else if */
- else if (signExtend16(pptr[i]->arg2) == -1)
- {
- pptr[i]->op = oINC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oNEQZ;
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oLT :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oLTZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i]->op = oDEC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oLTZ;
- nchanges++;
- } /* end else if */
- else if (signExtend16(pptr[i]->arg2) == -1)
- {
- pptr[i]->op = oINC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oLTZ;
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oGTE :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oGTEZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i]->op = oDEC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oGTEZ;
- nchanges++;
- } /* end else if */
- else if (signExtend16(pptr[i]->arg2) == -1)
- {
- pptr[i]->op = oINC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oGTEZ;
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oGT :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oGTZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i]->op = oDEC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oGTZ;
- nchanges++;
- } /* end else if */
- else if (signExtend16(pptr[i]->arg2) == -1)
- {
- pptr[i]->op = oINC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oGTZ;
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oLTE :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oLTEZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i]->op = oDEC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oLTEZ;
- nchanges++;
- } /* end else if */
- else if (signExtend16(pptr[i]->arg2) == -1)
- {
- pptr[i]->op = oINC;
- pptr[i]->arg2 = 0;
- pptr[i+1]->op = oLTEZ;
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- /* Simplify or delete condition branches on constants */
-
- case oJEQUZ :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+1]->op = oJMP;
- deletePcode(i);
- } /* end if */
- else
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
-
- case oJNEQZ :
- if (pptr[i]->arg2 != 0)
- {
- pptr[i+1]->op = oJMP;
- deletePcode(i);
- } /* end if */
- else
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
-
- case oJLTZ :
- if (signExtend16(pptr[i]->arg2) < 0)
- {
- pptr[i+1]->op = oJMP;
- deletePcode(i);
- } /* end if */
- else
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
-
- case oJGTEZ :
- if (signExtend16(pptr[i]->arg2) >= 0)
- {
- pptr[i+1]->op = oJMP;
- deletePcode(i);
- } /* end if */
- else
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
-
- case oJGTZ :
- if (pptr[i]->arg2 > 0)
- {
- pptr[i+1]->op = oJMP;
- deletePcode(i);
- } /* end if */
- else
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
-
- case oJLTEZ :
- if (pptr[i]->arg2 <= 0)
- {
- pptr[i+1]->op = oJMP;
- deletePcode(i);
- } /* end if */
- else
- deletePcodePair(i, (i+1));
- nchanges++;
- break;
-
- default :
- i++;
- break;
- } /* end switch */
-
- /* If the oPUSH instruction is still there, see if we can now */
- /* represent it with an oPUSHB instruction */
-
- if ((pptr[i]->op == oPUSH) && (pptr[i]->arg2 < 256))
- {
- pptr[i]->op = oPUSHB;
- pptr[i]->arg1 = pptr[i]->arg2;
- pptr[i]->arg2 = 0;
- } /* end if */
- } /* end if */
-
- /* Delete multiple modifications of DSEG pointer */
-
- else if (pptr[i]->op == oINDS)
- {
- if (pptr[i+1]->op == oINDS)
- {
- pptr[i]->arg2 += pptr[i+1]->arg2;
- deletePcode(i+1);
- } /* end if */
- else i++;
- } /* end else if */
- else i++;
- } /* end while */
-
- return (nchanges);
-
-} /* end unaryOptimize */
-
-/**********************************************************************/
-
-sint16 binaryOptimize(void)
-{
- sint16 nchanges = 0;
- register sint16 stmp16;
- register sint16 i;
-
- TRACE(stderr, "[binaryOptimize]");
-
- /* At least two pcodes are needed to perform the following binary */
- /* operator optimizations */
-
- i = 0;
- while (i < nops-2)
- {
- if ((pptr[i]->op == oPUSH) || (pptr[i]->op == oPUSHB))
- {
- if ((pptr[i+1]->op == oPUSH) || (pptr[i+1]->op == oPUSHB))
- {
- /* Turn the oPUSHBs into an oPUSHs op (temporarily) */
-
- if (pptr[i]->op == oPUSHB)
- {
- pptr[i]->op = oPUSH;
- pptr[i]->arg2 = pptr[i]->arg1;
- pptr[i]->arg1 = 0;
- } /* end if */
-
- if (pptr[i+1]->op == oPUSHB)
- {
- pptr[i+1]->op = oPUSH;
- pptr[i+1]->arg2 = pptr[i+1]->arg1;
- pptr[i+1]->arg1 = 0;
- } /* end if */
-
- switch (pptr[i+2]->op)
- {
- case oADD :
- pptr[i]->arg2 += pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oSUB :
- pptr[i]->arg2 -= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oMUL :
- pptr[i]->arg2 *= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oDIV :
- stmp16 = pptr[i]->arg2 / signExtend16(pptr[i+1]->arg2);
- pptr[i]->arg2 = stmp16;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oMOD :
- pptr[i]->arg2 %= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oSLL :
- pptr[i]->arg2 <<= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oSRL :
- pptr[i]->arg2 >>= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oSRA :
- stmp16 = (((sint16)pptr[i]->arg2) >> pptr[i+1]->arg2);
- pptr[i]->arg2 = (uint16)stmp16;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oOR :
- pptr[i]->arg2 |= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oAND :
- pptr[i]->arg2 &= pptr[i+1]->arg2;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oEQU :
- if (pptr[i]->arg2 == pptr[i+1]->arg2) pptr[i]->arg2 = -1;
- else pptr[i]->arg2 = 0;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oNEQ :
- if ((sint16)pptr[i]->arg2 != (sint16)pptr[i+1]->arg2)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oLT :
- if ((sint16)pptr[i]->arg2 < (sint16)pptr[i+1]->arg2)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oGTE :
- if ((sint16)pptr[i]->arg2 >= (sint16)pptr[i+1]->arg2)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oGT :
- if ((sint16)pptr[i]->arg2 > (sint16)pptr[i+1]->arg2)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- case oLTE :
- if ((sint16)pptr[i]->arg2 <= (sint16)pptr[i+1]->arg2)
- pptr[i]->arg2 = -1;
- else
- pptr[i]->arg2 = 0;
- deletePcodePair((i+1), (i+2));
- nchanges++;
- break;
-
- default :
- i++;
- break;
- } /* end switch */
-
- /* If the oPUSH instruction is still there, see if we can now */
- /* represent it with an oPUSHB instruction */
-
- if (pptr[i] && (pptr[i]->op == oPUSH) && (pptr[i]->arg2 < 256))
- {
- pptr[i]->op = oPUSHB;
- pptr[i]->arg1 = pptr[i]->arg2;
- pptr[i]->arg2 = 0;
- } /* end if */
-
- if (pptr[i+1] && (pptr[i+1]->op == oPUSH) && (pptr[i+1]->arg2 < 256))
- {
- pptr[i+1]->op = oPUSHB;
- pptr[i+1]->arg1 = pptr[i+1]->arg2;
- pptr[i+1]->arg2 = 0;
- } /* end if */
- } /* end if */
-
- /* A single (constant) pcode is sufficient to perform the */
- /* following binary operator optimizations */
-
- else if ((pptr[i+1]->op == oLDSH) || (pptr[i+1]->op == oLDSB) ||
- (pptr[i+1]->op == oLAS) || (pptr[i+1]->op == oLAC))
- {
- /* Turn the oPUSHB into a oPUSH op (temporarily) */
-
- if (pptr[i]->op == oPUSHB)
- {
- pptr[i]->op = oPUSH;
- pptr[i]->arg2 = pptr[i]->arg1;
- pptr[i]->arg1 = 0;
- } /* end if */
-
- switch (pptr[i+2]->op)
- {
- case oADD :
- if (pptr[i]->arg2 == 0)
- {
- deletePcodePair(i, (i+2));
- nchanges++;
- } /* end if */
- else if (pptr[i]->arg2 == 1)
- {
- pptr[i+2]->op = oINC;
- deletePcode(i);
- nchanges++;
- } /* end else if */
- else if (pptr[i]->arg2 == (uint16)-1)
- {
- pptr[i+2]->op = oDEC;
- deletePcode(i);
- nchanges++;
- } /* end else if */
- else i++;
- break;
-
- case oSUB :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i]->op = oNEG;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oMUL :
- stmp16 = 0;
- switch (pptr[i]->arg2)
- {
- case 1 :
- deletePcodePair(i, (i+2));
- nchanges++;
- break;
- case 16384 : stmp16++;
- case 8192 : stmp16++;
- case 4096 : stmp16++;
- case 2048 : stmp16++;
- case 1024 : stmp16++;
- case 512 : stmp16++;
- case 256 : stmp16++;
- case 128 : stmp16++;
- case 64 : stmp16++;
- case 32 : stmp16++;
- case 16 : stmp16++;
- case 8 : stmp16++;
- case 4 : stmp16++;
- case 2 : stmp16++;
- pptr[i]->op = pptr[i+1]->op;
- pptr[i]->arg1 = pptr[i+1]->arg1;
- pptr[i]->arg2 = pptr[i+1]->arg2;
- pptr[i+1]->op = oPUSH;
- pptr[i+1]->arg1 = 0;
- pptr[i+1]->arg2 = stmp16;
- pptr[i+2]->op = oSLL;
- nchanges++;
- i++;
- break;
-
- default :
- i++;
- break;
- } /* end switch */
- break;
-
- case oOR :
- if (pptr[i]->arg2 == 0)
- {
- deletePcodePair(i, (i+2));
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oAND :
- if (pptr[i]->arg2 == 0xffff)
- {
- deletePcodePair(i, (i+2));
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oEQU :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+2]->op = oEQUZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oNEQ :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+2]->op = oNEQZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oLT :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+2]->op = oGTEZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oGTE :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+2]->op = oLTZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oGT :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+2]->op = oLTEZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- case oLTE :
- if (pptr[i]->arg2 == 0)
- {
- pptr[i+2]->op = oGTZ;
- deletePcode(i);
- nchanges++;
- } /* end if */
- else i++;
- break;
-
- default :
- i++;
- break;
-
- } /* end switch */
-
- /* If the oPUSH instruction is still there, see if we can now */
- /* represent it with an oPUSHB instruction */
-
- if ((pptr[i]->op == oPUSH) && (pptr[i]->arg2 < 256))
- {
- pptr[i]->op = oPUSHB;
- pptr[i]->arg1 = pptr[i]->arg2;
- pptr[i]->arg2 = 0;
- } /* end if */
- } /* end else if */
- else i++;
- } /* end if */
-
- /* Misc improvements on binary operators */
-
- else if (pptr[i]->op == oNEG)
- {
- /* Negation followed by add is subtraction */
-
- if (pptr[i+1]->op == oADD)
- {
- pptr[i+1]->op = oSUB;
- deletePcode(i);
- nchanges++;
- }
-
- /* Negation followed by subtraction is addition */
-
- else if (pptr[i]->op == oSUB)
- {
- pptr[i+1]->op = oADD;
- deletePcode(i);
- nchanges++;
- }
- else i++;
- }
- else i++;
- } /* end while */
-
- return (nchanges);
-
-} /* end binaryOptimize */
-
-/**********************************************************************/
-
+/**********************************************************************
+ * pcopt.c
+ * Constant Expression Optimizations
+ *
+ * Copyright (C) 2008-2009 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ **********************************************************************/
+
+/**********************************************************************
+ * Included Files
+ **********************************************************************/
+
+#include <stdint.h>
+#include <stdio.h>
+
+#include "keywords.h"
+#include "pdefs.h"
+#include "pinsn16.h"
+
+#include "paslib.h"
+#include "popt.h"
+#include "polocal.h"
+#include "pcopt.h"
+
+/**********************************************************************/
+
+int16_t unaryOptimize(void)
+{
+ int16_t nchanges = 0;
+ register uint16_t temp;
+ register int16_t i;
+
+ TRACE(stderr, "[unaryOptimize]");
+
+ /* At least two pcodes are need to perform unary optimizations */
+
+ i = 0;
+ while (i < nops-1)
+ {
+ /* Check for a constant value being pushed onto the stack */
+
+ if ((pptr[i]->op == oPUSH) || (pptr[i]->op == oPUSHB))
+ {
+ /* Turn the oPUSHB into an oPUSH op (temporarily) */
+
+ if (pptr[i]->op == oPUSHB)
+ {
+ pptr[i]->op = oPUSH;
+ pptr[i]->arg2 = pptr[i]->arg1;
+ pptr[i]->arg1 = 0;
+ } /* end if */
+
+ switch (pptr[i+1]->op)
+ {
+ /* Delete unary operators on constants */
+ case oNEG :
+ pptr[i]->arg2 = -(pptr[i]->arg2);
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oABS :
+ if (signExtend16(pptr[i]->arg2) < 0)
+ pptr[i]->arg2 = -signExtend16(pptr[i]->arg2);
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oINC :
+ (pptr[i]->arg2)++;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oDEC :
+ (pptr[i]->arg2)--;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oNOT :
+ pptr[i]->arg2 = ~(pptr[i]->arg2);
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ /* Simplify binary operations on constants */
+
+ case oADD :
+ if (pptr[i]->arg2 == 0)
+ {
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i+1]->op = oINC;
+ deletePcode(i);
+ nchanges++;
+ } /* end else if */
+ else if (pptr[i]->arg2 == (uint16_t)-1)
+ {
+ pptr[i+1]->op = oDEC;
+ deletePcode(i);
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oSUB :
+ if (pptr[i]->arg2 == 0)
+ {
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i+1]->op = oDEC;
+ deletePcode(i);
+ nchanges++;
+ } /* end else if */
+ else if (pptr[i]->arg2 == (uint16_t)-1)
+ {
+ pptr[i+1]->op = oINC;
+ deletePcode(i);
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oMUL :
+ case oDIV :
+ temp = 0;
+ switch (pptr[i]->arg2)
+ {
+ case 1 :
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+ case 16384 : temp++;
+ case 8192 : temp++;
+ case 4096 : temp++;
+ case 2048 : temp++;
+ case 1024 : temp++;
+ case 512 : temp++;
+ case 256 : temp++;
+ case 128 : temp++;
+ case 64 : temp++;
+ case 32 : temp++;
+ case 16 : temp++;
+ case 8 : temp++;
+ case 4 : temp++;
+ case 2 : temp++;
+ pptr[i]->arg2 = temp;
+ if (pptr[i+1]->op == oMUL)
+ pptr[i+1]->op = oSLL;
+ else
+ pptr[i+1]->op = oSRA;
+ nchanges++;
+ i++;
+ break;
+
+ default :
+ i++;
+ break;
+ } /* end switch */
+ break;
+
+ case oSLL :
+ case oSRL :
+ case oSRA :
+ case oOR :
+ if (pptr[i]->arg2 == 0)
+ {
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oAND :
+ if (pptr[i]->arg2 == 0xffff)
+ {
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ /* Delete comparisons of constants to zero */
+
+ case oEQUZ :
+ if (pptr[i]->arg2 == 0) pptr[i]->arg2 = -1;
+ else pptr[i]->arg2 = 0;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oNEQZ :
+ if (pptr[i]->arg2 != 0)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oLTZ :
+ if (signExtend16(pptr[i]->arg2) < 0)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oGTEZ :
+ if (signExtend16(pptr[i]->arg2) >= 0)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oGTZ :
+ if (pptr[i]->arg2 > 0) pptr[i]->arg2 = -1;
+ else pptr[i]->arg2 = 0;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ case oLTEZ :
+ if (pptr[i]->arg2 <= 0) pptr[i]->arg2 = -1;
+ else pptr[i]->arg2 = 0;
+ deletePcode(i+1);
+ nchanges++;
+ break;
+
+ /* Simplify comparisons with certain constants */
+
+ case oEQU :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oEQUZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i]->op = oDEC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oEQUZ;
+ nchanges++;
+ } /* end else if */
+ else if (signExtend16(pptr[i]->arg2) == -1)
+ {
+ pptr[i]->op = oINC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oEQUZ;
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oNEQ :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oNEQZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i]->op = oDEC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oNEQZ;
+ nchanges++;
+ } /* end else if */
+ else if (signExtend16(pptr[i]->arg2) == -1)
+ {
+ pptr[i]->op = oINC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oNEQZ;
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oLT :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oLTZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i]->op = oDEC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oLTZ;
+ nchanges++;
+ } /* end else if */
+ else if (signExtend16(pptr[i]->arg2) == -1)
+ {
+ pptr[i]->op = oINC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oLTZ;
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oGTE :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oGTEZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i]->op = oDEC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oGTEZ;
+ nchanges++;
+ } /* end else if */
+ else if (signExtend16(pptr[i]->arg2) == -1)
+ {
+ pptr[i]->op = oINC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oGTEZ;
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oGT :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oGTZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i]->op = oDEC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oGTZ;
+ nchanges++;
+ } /* end else if */
+ else if (signExtend16(pptr[i]->arg2) == -1)
+ {
+ pptr[i]->op = oINC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oGTZ;
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oLTE :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oLTEZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i]->op = oDEC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oLTEZ;
+ nchanges++;
+ } /* end else if */
+ else if (signExtend16(pptr[i]->arg2) == -1)
+ {
+ pptr[i]->op = oINC;
+ pptr[i]->arg2 = 0;
+ pptr[i+1]->op = oLTEZ;
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ /* Simplify or delete condition branches on constants */
+
+ case oJEQUZ :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+1]->op = oJMP;
+ deletePcode(i);
+ } /* end if */
+ else
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+
+ case oJNEQZ :
+ if (pptr[i]->arg2 != 0)
+ {
+ pptr[i+1]->op = oJMP;
+ deletePcode(i);
+ } /* end if */
+ else
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+
+ case oJLTZ :
+ if (signExtend16(pptr[i]->arg2) < 0)
+ {
+ pptr[i+1]->op = oJMP;
+ deletePcode(i);
+ } /* end if */
+ else
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+
+ case oJGTEZ :
+ if (signExtend16(pptr[i]->arg2) >= 0)
+ {
+ pptr[i+1]->op = oJMP;
+ deletePcode(i);
+ } /* end if */
+ else
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+
+ case oJGTZ :
+ if (pptr[i]->arg2 > 0)
+ {
+ pptr[i+1]->op = oJMP;
+ deletePcode(i);
+ } /* end if */
+ else
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+
+ case oJLTEZ :
+ if (pptr[i]->arg2 <= 0)
+ {
+ pptr[i+1]->op = oJMP;
+ deletePcode(i);
+ } /* end if */
+ else
+ deletePcodePair(i, (i+1));
+ nchanges++;
+ break;
+
+ default :
+ i++;
+ break;
+ } /* end switch */
+
+ /* If the oPUSH instruction is still there, see if we can now */
+ /* represent it with an oPUSHB instruction */
+
+ if ((pptr[i]->op == oPUSH) && (pptr[i]->arg2 < 256))
+ {
+ pptr[i]->op = oPUSHB;
+ pptr[i]->arg1 = pptr[i]->arg2;
+ pptr[i]->arg2 = 0;
+ } /* end if */
+ } /* end if */
+
+ /* Delete multiple modifications of DSEG pointer */
+
+ else if (pptr[i]->op == oINDS)
+ {
+ if (pptr[i+1]->op == oINDS)
+ {
+ pptr[i]->arg2 += pptr[i+1]->arg2;
+ deletePcode(i+1);
+ } /* end if */
+ else i++;
+ } /* end else if */
+ else i++;
+ } /* end while */
+
+ return (nchanges);
+
+} /* end unaryOptimize */
+
+/**********************************************************************/
+
+int16_t binaryOptimize(void)
+{
+ int16_t nchanges = 0;
+ register int16_t stmp16;
+ register int16_t i;
+
+ TRACE(stderr, "[binaryOptimize]");
+
+ /* At least two pcodes are needed to perform the following binary */
+ /* operator optimizations */
+
+ i = 0;
+ while (i < nops-2)
+ {
+ if ((pptr[i]->op == oPUSH) || (pptr[i]->op == oPUSHB))
+ {
+ if ((pptr[i+1]->op == oPUSH) || (pptr[i+1]->op == oPUSHB))
+ {
+ /* Turn the oPUSHBs into an oPUSHs op (temporarily) */
+
+ if (pptr[i]->op == oPUSHB)
+ {
+ pptr[i]->op = oPUSH;
+ pptr[i]->arg2 = pptr[i]->arg1;
+ pptr[i]->arg1 = 0;
+ } /* end if */
+
+ if (pptr[i+1]->op == oPUSHB)
+ {
+ pptr[i+1]->op = oPUSH;
+ pptr[i+1]->arg2 = pptr[i+1]->arg1;
+ pptr[i+1]->arg1 = 0;
+ } /* end if */
+
+ switch (pptr[i+2]->op)
+ {
+ case oADD :
+ pptr[i]->arg2 += pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oSUB :
+ pptr[i]->arg2 -= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oMUL :
+ pptr[i]->arg2 *= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oDIV :
+ stmp16 = pptr[i]->arg2 / signExtend16(pptr[i+1]->arg2);
+ pptr[i]->arg2 = stmp16;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oMOD :
+ pptr[i]->arg2 %= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oSLL :
+ pptr[i]->arg2 <<= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oSRL :
+ pptr[i]->arg2 >>= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oSRA :
+ stmp16 = (((int16_t)pptr[i]->arg2) >> pptr[i+1]->arg2);
+ pptr[i]->arg2 = (uint16_t)stmp16;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oOR :
+ pptr[i]->arg2 |= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oAND :
+ pptr[i]->arg2 &= pptr[i+1]->arg2;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oEQU :
+ if (pptr[i]->arg2 == pptr[i+1]->arg2) pptr[i]->arg2 = -1;
+ else pptr[i]->arg2 = 0;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oNEQ :
+ if ((int16_t)pptr[i]->arg2 != (int16_t)pptr[i+1]->arg2)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oLT :
+ if ((int16_t)pptr[i]->arg2 < (int16_t)pptr[i+1]->arg2)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oGTE :
+ if ((int16_t)pptr[i]->arg2 >= (int16_t)pptr[i+1]->arg2)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oGT :
+ if ((int16_t)pptr[i]->arg2 > (int16_t)pptr[i+1]->arg2)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ case oLTE :
+ if ((int16_t)pptr[i]->arg2 <= (int16_t)pptr[i+1]->arg2)
+ pptr[i]->arg2 = -1;
+ else
+ pptr[i]->arg2 = 0;
+ deletePcodePair((i+1), (i+2));
+ nchanges++;
+ break;
+
+ default :
+ i++;
+ break;
+ } /* end switch */
+
+ /* If the oPUSH instruction is still there, see if we can now */
+ /* represent it with an oPUSHB instruction */
+
+ if (pptr[i] && (pptr[i]->op == oPUSH) && (pptr[i]->arg2 < 256))
+ {
+ pptr[i]->op = oPUSHB;
+ pptr[i]->arg1 = pptr[i]->arg2;
+ pptr[i]->arg2 = 0;
+ } /* end if */
+
+ if (pptr[i+1] && (pptr[i+1]->op == oPUSH) && (pptr[i+1]->arg2 < 256))
+ {
+ pptr[i+1]->op = oPUSHB;
+ pptr[i+1]->arg1 = pptr[i+1]->arg2;
+ pptr[i+1]->arg2 = 0;
+ } /* end if */
+ } /* end if */
+
+ /* A single (constant) pcode is sufficient to perform the */
+ /* following binary operator optimizations */
+
+ else if ((pptr[i+1]->op == oLDSH) || (pptr[i+1]->op == oLDSB) ||
+ (pptr[i+1]->op == oLAS) || (pptr[i+1]->op == oLAC))
+ {
+ /* Turn the oPUSHB into a oPUSH op (temporarily) */
+
+ if (pptr[i]->op == oPUSHB)
+ {
+ pptr[i]->op = oPUSH;
+ pptr[i]->arg2 = pptr[i]->arg1;
+ pptr[i]->arg1 = 0;
+ } /* end if */
+
+ switch (pptr[i+2]->op)
+ {
+ case oADD :
+ if (pptr[i]->arg2 == 0)
+ {
+ deletePcodePair(i, (i+2));
+ nchanges++;
+ } /* end if */
+ else if (pptr[i]->arg2 == 1)
+ {
+ pptr[i+2]->op = oINC;
+ deletePcode(i);
+ nchanges++;
+ } /* end else if */
+ else if (pptr[i]->arg2 == (uint16_t)-1)
+ {
+ pptr[i+2]->op = oDEC;
+ deletePcode(i);
+ nchanges++;
+ } /* end else if */
+ else i++;
+ break;
+
+ case oSUB :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i]->op = oNEG;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oMUL :
+ stmp16 = 0;
+ switch (pptr[i]->arg2)
+ {
+ case 1 :
+ deletePcodePair(i, (i+2));
+ nchanges++;
+ break;
+ case 16384 : stmp16++;
+ case 8192 : stmp16++;
+ case 4096 : stmp16++;
+ case 2048 : stmp16++;
+ case 1024 : stmp16++;
+ case 512 : stmp16++;
+ case 256 : stmp16++;
+ case 128 : stmp16++;
+ case 64 : stmp16++;
+ case 32 : stmp16++;
+ case 16 : stmp16++;
+ case 8 : stmp16++;
+ case 4 : stmp16++;
+ case 2 : stmp16++;
+ pptr[i]->op = pptr[i+1]->op;
+ pptr[i]->arg1 = pptr[i+1]->arg1;
+ pptr[i]->arg2 = pptr[i+1]->arg2;
+ pptr[i+1]->op = oPUSH;
+ pptr[i+1]->arg1 = 0;
+ pptr[i+1]->arg2 = stmp16;
+ pptr[i+2]->op = oSLL;
+ nchanges++;
+ i++;
+ break;
+
+ default :
+ i++;
+ break;
+ } /* end switch */
+ break;
+
+ case oOR :
+ if (pptr[i]->arg2 == 0)
+ {
+ deletePcodePair(i, (i+2));
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oAND :
+ if (pptr[i]->arg2 == 0xffff)
+ {
+ deletePcodePair(i, (i+2));
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oEQU :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+2]->op = oEQUZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oNEQ :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+2]->op = oNEQZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oLT :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+2]->op = oGTEZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oGTE :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+2]->op = oLTZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oGT :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+2]->op = oLTEZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ case oLTE :
+ if (pptr[i]->arg2 == 0)
+ {
+ pptr[i+2]->op = oGTZ;
+ deletePcode(i);
+ nchanges++;
+ } /* end if */
+ else i++;
+ break;
+
+ default :
+ i++;
+ break;
+
+ } /* end switch */
+
+ /* If the oPUSH instruction is still there, see if we can now */
+ /* represent it with an oPUSHB instruction */
+
+ if ((pptr[i]->op == oPUSH) && (pptr[i]->arg2 < 256))
+ {
+ pptr[i]->op = oPUSHB;
+ pptr[i]->arg1 = pptr[i]->arg2;
+ pptr[i]->arg2 = 0;
+ } /* end if */
+ } /* end else if */
+ else i++;
+ } /* end if */
+
+ /* Misc improvements on binary operators */
+
+ else if (pptr[i]->op == oNEG)
+ {
+ /* Negation followed by add is subtraction */
+
+ if (pptr[i+1]->op == oADD)
+ {
+ pptr[i+1]->op = oSUB;
+ deletePcode(i);
+ nchanges++;
+ }
+
+ /* Negation followed by subtraction is addition */
+
+ else if (pptr[i]->op == oSUB)
+ {
+ pptr[i+1]->op = oADD;
+ deletePcode(i);
+ nchanges++;
+ }
+ else i++;
+ }
+ else i++;
+ } /* end while */
+
+ return (nchanges);
+
+} /* end binaryOptimize */
+
+/**********************************************************************/
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-06 00:10:03 +0000